Apparatus for testing the strength of pasteboard, cardboard, and the like



Oct. 2?,1925- A. SCHOPPER APPARATUS FOR TESTING THE STRENGTH 0F PASTEBOARD, CARDBOARD, AND THELIKB Filed March 19, 1924 Patented 0a. 27, 1925. fjjj APPARATUS non. TESTING THE STRENGTH or PASTEBOARD, cAnnBoARn, AND 1m ALFRED scnorrnm orLEIPZI GERMAISTYJ' LIKE. v p

Application filed March 19, .1924. Serial No. 700,264.

To all whom it may concern: 7 Be it known that I, ALrnED siding at Leipzig, Germany, a citizen of the German Republic, have invented certain new and useful Improvements in Apparatus for Testing the Strength of Pasteboard,

Cardboard, and the like, of which the following is a specification.

A usualtype of apparatus bending and breaking strength oi paste board and the like comprises two holders, which are adapted to hold the sheet of board under test and co-operate with a spring whereby the torque necessary to bend and break such sheet may beascertained.

According to my invention the test piece is attached to two plates, which are rota table about a commonax'is, so that by 'moving them into an angular relation with each other the test piece is bent or broken, the rotation of one of the plates, from a position of rest, being opposed by a progressively increasing force due to a weighted pendulum or equivalent device, and means being provided for measuring the angle through which each plate is moved.

The accompanying drawings show by way of example an apparatus embodying the invention.

Fig. 1 is a side elevation of the complete apparatus, partly in section, and a v Fig. 2 shows, to a larger scale, the devicev in posts 7 and g, and the vaneshave edges parallel with the common axis of rotation.

The axle of the disc 03 carries a worm wheel h adapted to be rotated by a crank handle 2' and worm is. The axle of disc e carries a weighted pendulum Z which opposes rotation of said disc 6 from a normal'position of rest. When the discs are rotated, the angles through which they move are indicated by pointers 0 and p on scales m and n respectively, which are marked on the circumference of the said discs at and e. The diflerence between the angles of rotation of the Somme; re-.

for testingi the.

two discsis index to the"angleithrougli which the test-sheet has been bent. The test-sheet a1 is attached to against the test-sheet 0. by means of a thumb screw q. The members. 7". are guided obliquely to the planeof the vanes byineans of studss working in inclined slots t, This ar-, rangement has the effect that the distance between the two clamping members p is a1 v ways in a predetermined relationj to the thickness (Z of thetest piece-,sayj-in the pro p tio 0 5. 1 nsfiqn n' ythe esu t btained with boards of "different thicl'znesses are directly'comparable. I

The edges of the clamping portions of the I theftwo. vanes 5 and 0 by means of theltwo cl'amps shown .in' Fig. 2,.each of which comprises a clamping member 1 adapted to be pressed;

vanes b and c are shown in Fig/2m contact 7 or very nearly in contact with each other; if they are apart the distance between them is only just sufficient to allow of free movement of the clamping members.

In consequence of this arrangement the outer layer of the test sheet, on one side, is

not subjected to any tensile strain during the bending test. In Fig. 2 the contactin edges coincide with the common axis .or rotation.

A cord at is secured with its ends to the discs d and e, and passes over a series of pulleys, This cord carries a style, .10 arranged to move along a recording drum o, when the cord is moved by rotation of the discs. The movement of the style w records the differential rotary movementof the discs (Z and 0. disc 6, which corresponds to the bending stress of the test-sheet, is transmitted to the.

In addition, the rotation of the.

recording drum 4; by means of a cord m at-' r tached to the disc 6 and engaged with a pulley e on the spindle of thedrum 0.

It will beevident that instead of'the pendulum Z I may use any other equivalent '1 means. I 7

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is 1. In apparatus for the purpose set forth axis, means for attaching a test piece to both sa1d plates,-means opposln'g progresa slvely increasing resi'stance'to the'rot'atron' oione of said plate carriers from a position-0frest, means for imparting rotation tothe other plate carrier, and means for measuringithe 'rotation imparted to said plate carriers respectively. 7,

2. In apparatus for the purpose set forth the combination of two plates; t'w'o rotatable carriers forsaid plates whereby saidplates a're'*rota-table'aboirt a Common axis; means" for attachingfa t' estpiec 'e to both said plates, a"W'eighted pendulum fixed to Onebfsa-id p'late carriers; means-for imparting rotation to th'e' othe'r' plate carrier, and means for measuring the rotation imparted to said platecarriersrespectively;

, 3E In -apparatus for'the purpose set forththe combination of two plates, two rotatable carriers" for said plates, whereby said platesare rot'atalil'e-abouta common axis,- two clamping" devices, .o ne onleach plate eachi'n'cludinga clamping member movable to and from the plate" surface" and an oblique guide for said clamping member, whereby the distance between the clamping member and the common axis OfIOtatIOD is reduced asthe member 'ap'proaches the plate surface,

means opposing progressively increasing resistance tothe rotation of one of said plate carriers from a position of rest, means for imparting rotation to the other platecarrier, and means for measuring the rotation imparted to said plate carriers respectively.

45 In apparatus for the purpose set forth the combination of two plates, tWo rotatable carriers for said plates whereby said plates are; rotatable about-a common'aXis, each of said plates-having FRED: soHo iPP'ER;

an'eclge Which-coin ides wrthszudams of rotation; means fora-t 

